The present invention relates to dispensers for a flowable material, such as toothpaste.
Conventionally, toothpaste has been sold in squeezable tubes. Recently, dispensers for toothpaste have been introduced in which the toothpaste is pumped from a chamber through an outlet orifice. Although these dispensers work satisfactorily, it is desirable to determine when the chambers of the dispensers are nearly empty to indicate when the dispensers should be discarded and another one be purchased. Dispensers are disclosed in U.S. Pat. Nos. 4,437,591 and 4,461,403, incorporated herein by reference.